Bootstrap is a free and open-source CSS framework directed at responsive, mobile-first front-end web development. It contains CSS and JavaScript-based design templates for typography, forms, buttons, navigation, and other interface components.
cdnjs is a free distributed JS library delivery service.
Google Tag Manager is a tag management system (TMS) that allows you to quickly and easily update measurement codes and related code fragments collectively known as tags on your website or mobile app.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
ipify is a service which provide public IP address API, IP geolocation API, VPN and Proxy detection API products.
MaxMind is a provider of geolocation and online fraud detection tools.
PayPal is an online payments system that supports online money transfers and serves as an electronic alternative to traditional paper methods like checks and money orders.
Pingdom RUM(Real User Monitoring) is a feature of the Pingdom website monitoring and performance testing service. RUM enables you to collect and analyse data on how real users are experiencing your website.
reCAPTCHA is a free service from Google that helps protect websites from spam and abuse.
Salesforce Desk(Desk.com) is software as a service (SaaS) tool on the help desk.